Several types of fiber optic systems can have fiber optic components on more than one fiber optic tray. This is especially the case especially in systems designed for occupying a limited volume. It was known for instance in the field of lasers or amplifiers using fiber optics to mount the fiber optics on several superposed trays in a fixed structure. However, such designs had maintenance limitations including the fact that when a component of the system broke, a relatively large portion of the stack required disassembly to allow replacing the component, which led to undesirably high maintenance-associated costs.
Optical fibers have particular handling characteristics. One of these is the fact that during use, they can be curved to a certain extent, but bending past a critical radius will likely affect the light transmission ability. The critical radius is a specification of optical fibers which are typically made available to designers, so that fiber optic systems can be designed with optical fiber paths which avoid having areas of curvature which are inferior to the critical radius of the given fiber it is intended to receive. Another of these is that optical fibers have a limited tolerance to mechanical stress and are relatively fragile. It was therefore known, for instance, to design an optical fiber path in a fixed stack fiber optic laser which transited from one tray to the next in a progressive fashion.